Method of making venetian blind slats



Aug. 18, 1953 sxr. CUMMING METHOD OF MAKING VENETAIN BLIND SLATS 4 Sheets-Sheet 1 Filed Aug. 2, 1948 INVENTOR. 6'60 4 Ida/770mg Aug. 18, 1953 G. T. CUMMING 2,649,393

7 METHOD OF MAKING VENETAIN BLIND SLATS Filed Aug. 2, 1948 4 Sheets-Sheet 2 INV TOR. 'eorye 7. 4107mm;

x ws ggwzg I ATTORNE.

Aug. 18, 1953 e. T. CUMMING METHOD OF MAKING VENETAIN BLIND SLATS 4 Sheets-Sheet 3 Filed Aug. 2, 194a INVENTOR. George ZZZ/mm? BY Aug. 18, 1953 G. T. CUMMING METHOD OF MAKING VENETAIN BLIND SLATS 4 Sheets$heet 4 Filed Aug. 2, 1948 4 TTORNE M m ma WM 6 W e 6 Patented Aug. 18, 1953 UNITED STATES PATENT OFFICE METHOD OF MAKING VENE'I'IAN BLIND SLATS George T. Cumming, Kansas City, Mo., assignor to William Volker and Company of Missouri, Inc., Kansas City, Mo., a corporation Application August 2, 1948, Serial No. 41,936

Claims.

affixed thereto.

The most important object of this invention is to provide the method of manufacturing Venetian blind slats including the steps of continuously feeding the tape along a predetermined path of travel while simultaneously feeding a pair of wires along one face of said tape and joining the wires and the tape as the same progress together.

Another important object of this invention is to provide a Venetion blind slat utilizing a tape made from material readily fusible upon itself to the end that in the method of manufacture, the tape may be readily secured to the reinforcing wires by the simple step of folding the tape over the wires and applying heat thereto to the end that the folded portions automatically fuse upon the remainder of the tape.

Another important object of this invention is the provision of a method of producing Venetian blind slats of the kind above set forth wherein is included the step of stretching the tape longitudinally and holding the same in a flat condition transversely as the tape and wires are being interconnected, all to the end that the tape itself will be flat and devoid of wrinkles in the finished slat.

A further object of this invention is the provision of a method of producing a particular type of Venetian blind slat wherein those portions of the tape that are folded over the reinforcing wires to present a hem or piping for the wires, are held down tightly against one face of the tape upon which such portions are used from the time such folding initially takes place and until the fusion is completed, all without interjoined wires and tape into predetermined slat lengths after the tape stretching step has been completed and after the wires no longer need to be held in spaced apart relationship, said severing step including the compensation for steady movement of the tape and wires as the cutting means causes momentary retardation of slat movement.

A still further important object of this invention lies in the step of feeding the wires and the tape at difierent speeds to the end that the lengths of the Wires and tape in the completed slat will be of uniform difference irrespective of the length of slat that is severed.

Many additional more minor objects of this invention will become clear as the following specification progresses and in carrying out the method, one embodiment of apparatus capable of carrying out the steps of the method is herein disclosed and will hereinafter be fully described. Such apparatus forms the subject matter of my copending application Serial No. 41,935, filed August 2, 1948, and entitled Machine for Producing Venetian Blind slats. This machine is illustrated in the accompanying drawing, wherein:

Fig. l is a side elevational view of a portion of a machine for producing Venetian blind slats following the method of the present invention.

Fig. 1a is a side elevational view illustrating the remainder of said machine.

Fig. 2 is a transverse cross sectional view taken on line IIII of Fig. 1 looking in the direction of the arrows.

Fig.3 is a cross sectional view taken on irregular line IIIIII of Fig. 2, parts being broken away for clearness.

Fig. 4 is a fragmentary cross sectional View taken on line IV-IV of Fig. 1.

Fig. 5'is a fragmentary top plan view showing the means for folding the marginal edges of the tape forming a part of the slat over the reinforcing wires thereof.

Fig. 6 is a fragmentary side elevational view showing the tape folding means illustrated in Fig. 5.

Fig. '7 is a fragmentary side elevational view illustrating the tape cutting means per se.

Fig. 8 is a detailed cross sectional view taken on line VIIIVIII of Fig. 1a, looking in the direction of the arrows.

Fig. 9 is a fragmentary cross sectional view taken on line IX-IX of Fig. 1a. looking in the direction of the arrows.

Fig. is a fragmentary detailed cross sectional view taken on line XX of Fig. 1a.

Fig. 11 is a fragmentary cross sectional view taken on line XIXI of Fig. 1.

Fig. 12 is a side elevational view of the structure illustrated in Fig. 11 showing the side opposite to that illustratedv in Fig. l of, the drawing.

Fig. 13 is a detailed cross sectional view taken on line 2C[IIXIII of Fig. 7 looking in the direction of the arrows. i

Fig. 14 is a perspective view of allenetianblin slat to be produced by the machine formingthe; subject matter of this invention, the slat illustrated in Fig. 14 being only partially formed for clearness.

Fig. 15 is a perspective view of the Venetian blind slat completely formed. I 7

Fig. 16 is an end view of the slat; and

Fig. 17 is a transverse cross sectional viewtaken on line XVIIXVII of Fig. 15.

The Venetian. blind slat contemplated to; be manufactured by the method formingthesubject matter of; this invention differs from. the; common type of slat. generally known in that the same; is at least partially flexible and definitely not rigid as in the case. of a wood or; metallic paneL. This slat is elongated in the usual manner as illustrated in Figs. 14 and 15 and includes a pair of substantially parallel, elongated reinforcing members I0 and I2 disposed along the longitudinal edges of the slat, the latter of which iszgenerally designated by the numeral I4. These. two wires Ill and i2 havesecured thereto an elongated strip of tape I6.

This tape It is made from flexible material that is somewhat pliable. and ductile and also slightly elastic within limits. Such materialmay constitute a fabric or a combined textile and paper roduct. commonly used on ordinary window shades or. any other material capable of use with amachine' such as that about tobe described informing the Venetian blind slat I4 and by=the method. formin the subject matter or this invention.

Another characteristic of the material from which the tape I6 is formed is. that it is readily fusible upon itself upon application of heat thereto, the fabric, or other. material usedbeing, during manufacturetherefof, treated with adhesive substances. As will hereinafter be more fully set forth, this characteristic is extremely adva'n tageous since. the longitudinal marginal edges of tape I 6 are. folded over the'c'orres'pofiding wires If! and I2 to lie flatly against one face I3; of tape I6 and these folded edges 2c and 22. are held tightly upon face I8 while heat isfapplied thereto to the end that they adhere tightly'to. said face I8.

It is seen that a hem is formed in the tape I6 along the two longitudinal marginal edges thereof presenting pipings or tubular portions 24' and 25 for receiving the wires I9 and I2 respectively. The joined tape I6 and wires It and I2: are. cut into desired lengths as illustrated in Fig. 15 by the machine about to be described and as; hereinafter more fully set forth.

A pair of spaced apart elongated openings 28 are formed in the blind i4 and particularly in that portion thereof between the wires I10. and I2 and the marginal edges. of the overlapped portions Hand 22. thereof, said slots 28. having: their longitudinal axes runnin transversely of. slat IA. Each of these openings 28 is providedwitlr av clip 30 disposed. on the face of; the. blind Illv opposite to face I8 thereof and spanningthe distance bejings.

tween the two reinforcing rods or wires Ill and I2 and the pipings 24 and 26. This clip 30 has its ends provided with ears 32 that partially circumscribe the pipings 24 and 26 and the wires I0 and I2 respectively encased therein. The ends of the clip 30 between the two ears 32 thereof overlap the portions 20 and 2210f the tape I6; and abut the. innermost edges of. the. pipings. 22 and 24, all as clearly illustrated in Fig. 17 of the draw- It is thus seen that the ears 32 of clip 30 hold the Wires I0 and I2 against separation and that. the 'ends of the clip 30 prevent inward movement of the wires I0 and I2 toward each other...

Itiis contemplated that mounting of the clips 3I11ipbn the slat I 4 constitute the last operation andbe. accomplished by a specially formed mechanism capable of automatically stamping the openings? in the tape I6 and a registering opening 34 in each clip 30 of the same contour as openings 28. Thusv the clip 3.8; also serves as a reinforcing means for the. openings 28, thelatter. ofv which. receive the Venetial blind elevating ropes in the usual manner..

The machine capable of following the method ofmaking. the Venetian. blind slat It just described illustrated inEigs. land 1a of the drawing, includes a framework broadly designated by the numeral. 36; having. a plurality of supporting legs, 38 disposed in spaced. apart relationship throughout its length. As. is; readily seen in these two figures, the machinev generally elongated and they framework 3.5 supports all of the component parts thereof. I

The. flexible tape I6. is carried in a roll 30 adjacent one end of the machine and this roll M) is rotatably supported by a bracket d2 depending from. the. frameworktfii. Tape I6 is fed from the roll- .48 along the entire: length of the framework 36 ina substantially rectilinear, horizontal path of travel, tape t6 passing first over an arcuate guide. member 44.. From this. guide member is the tape. H5. is directed over' a; supporting plate is which carries a. pressurefplate itv beneath which tape I6 travels. This pressure plate 48 is of conventional character and; isprovided with a plurality of upstanding, pins: 50. serving. as a means for shiftably securing: plate 48 to plate 45, said pins. 5.0 being. provided with springs to yieldably hold tape t6 tightly,. yetf-reely slidable upon the uppermost face; of. plate 46.. From these plates 46 and the tape: I6, passes into a foldingv means therefor designated. by the numeral 52 and hereinafter more fully described. Simultaneously with. the feeding of the; tape it, from roll it, the pair of spaced apart wires III and I2; are. also fed upon theface I8 of tape t6; These wires Ill and I2 are directed into the machine from continuous rolls; suitablyv supported by means not herein illustrated. These-Wires It and I2 first pass between pairs of. spaced apart rollers 5 and 55 disposed, as illustrated inFig. 11, adjacent one endof the machineproximal to the roll 49 of: tape Iii and, formed as moreclearly illustrated in Fig. 11 of the drawing.

' A hollow housing 58 mounted in upstanding relationship upon. the framework. as rotatably receivesta shaft. having, a bevel. gear 62 onone end; thereof externally of housing 58. one of the rollers and oneof the. rollers 56 aremounted upon this. shaft 60. and: are. rotatable therewith. These rollers are in spaced. apart relationship as illustrated in Fig. 11. 1 A painof. U-shaped brackets 66 disposed with n the honsinsifl have bearings adjacentthe free ends of the legs thereof for receiving a shaft 64 that joins opposed side walls of housing 58 as Seen in F 12, said legs being substantially triangular-shaped as partially iilustrated in Fig. 12 of the drawing. Each of these uppermost rollers 54 and 56 is provided with a stubshaft joining the legs of the respective bracket 56 and rotatably mounted in another set of bearings spaced from the bearings for the shaft 84.

Gears 68 and I are formed on all the rollers 54 and 56 respectively adjacent one edge thereof, the gears of the uppermost rollers being enmeshed with the gears of the lowermost pair of rollers on shaft 60 as illustrated in Fig. 11 of the drawings and yieldably held in such meshing relationship by a pressure plate I2 overlying the two brackets 66, there being a pair of coil springs I4 .interposed between the plate I2 and the uppermost face of the bights of bracket 88.

Pressure plate 12 has an upstanding pin I5 slidably mounted in the housing 58 and extending upwardly between a pair of brackets 16 mounted upon housing 58. These two brackets I6 have swingably secured thereto by pin '78 an elongated arm 80 having a cam portion 82 bearing against the uppermost end of the pin I5 and serving to release the uppermost rollers 54 and 56 when arm 80 is swung upwardly from the position illustrated in Figs. 11 and 12 of the drawing. All of the rollers 54 and 55 are provided with a plurality of annular grooves 84 disposed in substantially parallel relationship and extending outwardly from the gears 68 and Ii! thereof. The grooves of the lowermost rollers register with the grooves of the uppermost rollers and pro- 5.

gressively decrease in depth as the gears 68 and '10 of the rollers are approached.

The wires I0 and I2 of the slat I4 are directed between selected pairs of the grooves 84 after passing through a guiding means 86 extending outwardly from the frame 35 as illustrated in Fig. 1. Obviously, the combined diameter of any pair of grooves 84 is less than the diameter of the wires I0 and I2 to the end that a frictional grip is imparted to the wires I0 and I2 by the rollers 54 and 56 because of the provision of springs 14. Since these grooves 84 are of differing diameters, the speed at which the wires I0 and I2 are fed into the machine upon rotation of shaft 60 and consequently the rollers 54 and 56 will depend entirely upon which of the pairs of grooves receives the wires. The rollers 54 and 56 feed the wires I0 and I2 directly into a wire straightener 88 and since this straightener 88 may be of conventional character, the same has not been detailed and need not be described.

As illustrated in Figs. 5 and 6 of the drawings, the wires I0 and I2 are directed between the plates 46 and 48 directly upon the uppermost face of the tape I8 which is the face I8 thereof illustrated in Figs. 14 to 1'7 inclusive of the drawings. Fig. 5 also illustrates the manner in which the wires I0 and I2 are in substantially parallel relationship and spaced from the respective outermost marginal edges of the tape I6. The distance at which these wires I0 and I2 are so spaced determines the width of the slat I 4 shown in Figs. 14 and 15. The folding means 52 which extends forwardly from the pressure plate 48 constitutes an initially flat strip of material formed from a bendable metallic substance, one end thereof being adjacent the pressure plate 48 and having a width substantially the same as the width of the tape I6. The longitudinal marg nal edges of the opposite end of this folding means 52 are rebent upwardly and inwardly as at 90 to present spaced apart troughs for receiving and causing the marginal edges of the tape I6 to fold upon themselves over the wires I0 and I2. The distance between these troughs formed by the overlapping portions 90 of the member 52 adjacent the outermost free end thereof is substantially the same as the distance between the wires I0 and I2. It is thus seen as the wires I0 and I2 in the tape I6 progress together through the forming means 52, the portions 20 and 22 of tape I6 will form a pair of hems that completely encompass the two wires I0 and I2 forming the piping-s 24 and 26. From the forming means 52, the wires I0 and I2 and the tape I6, pass beneath another pressure plate 92 yieldably bearing against the tape I6 and formed in much the same manner as the plate 48 and its component parts. The tape and wires progress from the pressure plate 92 into an elongated channel member 94 (Figs. 2, 3 and 4).

This channel member 54 as illustrated in Fig. 2 of the drawings, constitutes a pair of L-shaped strips presenting upstanding side walls which are spaced apart a distance substantially the same as the width of the completed slat I4 shown in Fig. 15 of the drawing.

A plurality of roller assemblies (Figs. 2 and 3). are disposed throughout the length of the frame 36 for receiving the tape and the wires, after the former has been folded in the manner above described. These assemblies broadly designated by the numeral 96, include a polygonal framework 91 provided with a pair of spaced apart substantially parallel horizontal shafts 98 and I00, both .of which are journaled for free rotation in the framework 91. These two shafts 98 and I00 traverse the path of travel of the tape I6 and its wires I0 and I2. The guide channel 94 is disposed between the shafts 98 and I00 and is provided with openings I06 for receiving a roller I04 that is secured to the shaft I00. In other words, the rollers I04 of all of the assemblies 98,

extend upwardly through openings I06 of channel member 94.

The assemblies 96 are all provided with a U shaped bracket I08 formed in much the same manner as the brackets 66 illustrated in Fig. 11 of the drawings in that the legs thereof are subswingable therewith.

Spaced from the shaft 98 and in substantially parallelism therewith is a horizontal stubshaft H0 spanning the distance between the legs of the bracket I08 and journaled in suitable bearings. This stub shaft II!) has a roller I02 secured thereto, said roller I02 being disposed between the legs of the bracket !68 and in opposed relationship directly above the roller I84 of shaft I00. One end of the shaft I00 extends outwardly beyond the framework 91 and has a bevel gear II 2 mounted thereon. A pair of gears I I4 and H5 on shafts H0 and I00 respectively, are in meshing relationship and held in this position by a coil spring I I8 disposed between the upper most face of the bracket I08 and a bolt I20 threadably mounted in the uppermost wall of framework 91.

It is clear that the tension of spring I I8 may be adjusted by manipulation of the bolt I20 determining also the extent of the frictional pressure which the roller I02 imparts to the tape I6 and the overlapping portions 20 and 22 thereof.

In other words, this tape I6 passes between the rollers I62 and I04 which are driven at the same rate of speed by virtue of the bevel gear H2 and the two intermeshing gears H4 and H6. The rollers I62 and I64 are of substantially the same diameter but these rollers of the assemblies 95 progressively increase in diameter as the fed end of the tape is approached. In other words, the rollers I62 and I64 of the assemblies 96 first receiving the tape I6 are of a given diameter sufiicient to impart a frictional grip to the tape I6 and to move the same along the framework 66 within the channel 94. As the tape I6 reaches the second assembly 96, the rollers I62 and I64 thereof having a slightly greater diameter, a greater pressure or gripping force will be imparted to the tape I6 and an increased pull exerted thereon. This same, increase in pull and driving force for the tape I6 is present in the third and fourth assemblies 96 but progressively increasing in value. It is thus seen that all of the assemblies 66 cooperate in driving the tape I6 along its horizontal path of travel, but because of this difference in the diameters of the rollers I62 and I64 of the respective assemblies 96, a longitudinal stretching force is imparted to the tape I6 itself. This stretching force is present throughout the entire length of the tape I6 between the first assembly 96 and the last assembly 96 along the framework 36.

It is to be understood further that additional adjustment of this pulling and stretching force upon the tape I6 can be made by manipulation of the bolts I26.

Interposed between the first and the second assemblies 96 is heating structure (Fig. 42) broadly designated by the numeral I22. This heating structure I22 includes an uppermost plate I26 preferably of asbestos or other insulating material and a body I26 provided with a cavity I28 within which is provided an electric heating element I36. This body I26 is made from any good heat conductor and has a pair of down-turned ribs I32 extending therefrom, said ribs I32 being spaced apart a distance substantially the same as the distance between the overlying portions 29 and 22 of the tape I6. The lowermost edges of these ribs I32 are spaced slightly above the channel member 94 and as the tape progresses through the structure I22, heat emanating from element I36 will cause the portions 26 and 22 of tape I6 to fuse upon the face I8 thereof.

As above mentioned, the first assemblies 26 serve to hold the portions 20 and 22 tightly against the face I8 of the tape I6 prior to passage thereof into the structure I22 and as the tape progresses outwardly from the heating structure I22, the next assembly 66 will hold the portions 26 and 22 tightly in place until the tape I6 cools and the portions 26 and 22 rendered capable of adhesion without support.

As illustrated in Fig. 2 of the drawing, the width of the rollers I02 and I64 is substantially the same as the distance between the wires i6 and I2, thus serving as a means for holding the wires I6 and I2 in substantially parallel spaced apart relationship. By the time the wires I6 and I2 and the tape I6 secured thereto, reaches and passes beyond the last assembly 96 where stretching is no longer applied to the tape I6, the overlapping portions 20 and 22 will be tightly secured in place with the wires I and I2 within the pipings 24 and 26. The bevel gear 62 is disposed in alignment with all of the bevel gears I I2 of assemblies 96 and are actuated bya common. drive constituting an elongated shaft I 34 extending substantially the entire length of the frame 36 and in a horizontal position. The shaft I34 has a small bevel gear I36 for each of the bevel gears I I2 and. for the bevel gear 62 respectively.

Any suitable means such as an electric motor or the like I38 maybe used to drive the shaft I34. This motor I38 is mounted directly upon the framework 36 and has its drive shaft I46 joined to the shaft I34 by means of a plurality of shafts, pulleys and belts or the like broadly designated by the numeral I42 and interconnected in the conventional manner. Belts I43 join pulleys mounted upon shaft I46 of motor I36 and corresponding pulleys forming a part of the wire straightener 88 and serve to drive the latter in the usual manner. The joined tape and wires are fed into a cutting means (Fig. 7) broadly designated by the numeral I44 including a stationary cutting blade I46 and a vertically reciprcsable cutting blade I48. This reciprocable blade I48 is driven by an electric motor or the like I56 (Fig. la) that drives a relatively large pulley I52. Conventional interconnection between pulley I52, the shaft I54, upon which it is mounted, and the movable cutter I46, causes reciprocation of the latter. It is contemplated that an over-drive as sembly form a part of the cutting means I44. Since this means for imparting vertical reciprocation with great force to. the blade I66 is of conventional character and forms no part of the subject matter of this invention, the same is not illustrated in detail and need not be described.

From the channeled track 94, the joined tape I6 and wires I6 and I2 project between the normally spaced apart cutters I46 and I48 into a track I56 extending outwardly beyond the cutting means I44 and mounted upon the framework 36. This track I56 constitutes a pair of spaced apart members I58, each of which is L- shaped in cross section as shown in Fig. 3. A number of lugs I53 removably secured to one of the members I 58 has an L-shaped plate I55 joined thereto, which plate I55 has one leg thereof spanning the distance between the .members I58 in overlying relationship thereto.

A plurality of upstanding U-shaped brackets I66 mounted upon the framework 36 in spaced apart relationship, have elongated rods I62 and I64 journaled in the legs thereof. These rods I62 and I64 are spaced apart and disposed above the track I56. The rods I62 and I64 support a number of opposed dogs I66 and it is upon these dogs I66 that the members I56 of track I56 are mounted. Dogs I66 are normally in the position illustrated in Figs. 9 and 13 where the members I56 are in a position for receiving the tape I6 and its wires I6 and I2 and as rods I62 and I64 are caused to rotatev in one direction, the dogs I66 will move apart, thereby moving the members I56 apart and permitting dropping or feeding of the cut slat I4 from plates I55;

Means: for causing rotation of the rods I62 and I64 constitutes opposed links I66 secured directly to the rods I62 and I64 and extending inwardly toward each other in overlying relationship to the track I56. The innermost free ends of these links I68 are provided with rollers I'll).

A vertically reciprocable member I22 forming a part of the cutting means I44 has a. cam member I" secured directly thereto as shown in Fig. 7, this cam member I14 depending down- .9 wardly between the links I68 and bearing against the opposed rollers I10. It is clear that as the member I12 moves downwardly to shift-cutter I48 to a point where it cooperates with the rigid cutter I46 in severing the tape I6 and wires I and I2, cam I'M will also move downwardly be' tween the rollers I10, spreading the same apart causing rotation of the rods I62 and I64 and thereby spreading the dogs I66 to'release the cut slat I4. Upstanding pins I16 on rods I62 and I64 have their uppermost ends joined to the respective bracket I60 by means of a spring I18 for yieldably holding the dogs I66 in the position illustrated in Fig. 13. The cut slats I4 will fall directly upon the uppermost of framework 36 or, if desired, a receiving tray therefor (not shown) may be provided.

The bights of the brackets I60 are joined by an elongated bar I80 provided with a longitudinal slot I82. A U-shaped bracket I84 overlies this bar I80 and overlaps the sides thereof, this bracket I84 being provided with a pair of arms I86 depending therefromon each side of the bar E88 (see Fig.

A pin I 88 mounted upon one of the arms I86 extends into the slot I82 of bar I80. Manually operable clamping means I90 serves to shiftably secure the bracket I84 and its component parts directly to the bar I80. As noted in Fig. 10 of the drawing, arms I86 extend downwardly between the rods I62 and I64 and have secured thereto a plate I92 that projects downwardly between the L-shaped members I58. This plate I92 is connected electrically in a conventional manner to the motor I50 and since plate I92 is directly within the path of travel of the-tape I6 and the wires I0 and I2, as soon as contacted a circuit is closed through the motor I50 to operate the cutting means I44 as well as the cam member I14 for releasing the cut slat I4. Since the bracket 584 is shiftably mounted upon the elongated bar ifiii, the length of the slat I4 may be selected. Also, this bracket E84 is removably mounted upon 89 to the end that the same may be moved to a point between any two of the brackets I68. Inasmuch as the wires I0 and I2 and tape I6 are continuously and simultaneously fed through the machine by common driving means, each time the blades I46 and I48 of cutting means I44 come into operation, the movement of the tape I6 and wires I0 and I2 would ordinarily be momentarily stopped. Accordingly, compensation is made for buckling of the tape and wires during each cutting operation. This buckling effect amounts to an upward bending of the tape and wires in the manner illustrated in Fig. 1 of the drawings, said buckling taking place between the last of the assemblies 96 and the cutting means I44. At this point of upward flexing or bending of the tape and wires momentarily during each cutting operation is disposed a pair of spaced apart upstanding walls I94 to guide the tape and wires as the same moves upwardly.

While the operation of the machine has been fully described throughout the above description of the component parts thereof, a brief summary of the operation of the machine is asfollows:

The wires I0 and I2 areflfed continuously through the rollers 54 and 56 while the tape I6 It is desired that the ends of the wires I0 and I2 of the slat I4 be disposed a slight distance inwardly from the end of the tape I6 and consequently, such adjustment can be made by selecting the grooves 84 into rollers 54 and 56 in which the wires I0 and I2 are disposed. These grooves 84 therefore, compensate for differing lengths of slats I4. In other words, as the switch plate I92 is shifted whereby slats I4 of different lengths are cut, the distance at which tape I8 projects beyond the ends of the wires I0 and I2 will accordingly vary because of the common drive for the tape and the wires.

It is a simple expedient to actuate the lever 80 and to change the wires I0 and I2 moving the same into grooves 84 of diiferent diameters. After the strips are cut into predetermined lengths, they may subsequently be placed into another machine (not shown) for mounting the clips 30 and forming the openings 28 and 34 as above described.

While all of the steps of the method of making Venetian blind slats have become apparent through the above description of apparatus capable of carrying forth such method, the steps can be briefly outlined in the following manner:

Obviously, the first step of the method constitutes directing the tape and the wires simultaneously through a given path of travel with the wires disposed upon one face of the tape in spaced apart relationship to the longitudinal marginal edges of the tape and with the wires substantially parallel. It is advantageous to utilize a common driving means for the tape and wires as accomplished through the apparatus herein described and, therefore, another step in the method lies in controlling the speed of travel of the wires with respect to the speed of travel of the tape. Withsuch control, the resultant slat will have its Wires spaced slightly inwardly from the ends of the tape irrespective of the length of the particular slat that is severed.

The next step in the method is to fold the marginal edges of the tape over the two spaced apart wires to present pipings for the wires and also to form portions of the tape which are to be subsequently joined to said one face of the tape. After the folding and hem forming operation has taken place, the heating process comes into action to cause fusing of the overlapping portions of the tape to the proximal face thereof.

It is understood that the method includes the step of holding the hem forming portions of the tape tightly against one face thereof not only before the same pass in the heating structure but after the joint tape and wires move toa point where cooling is possible.

These operations or steps, together with all of the other following steps are carried out while the tape and wires progress without any interruption whatsoever. 7

Another step in the method lies in the longitudinal stretching of the tape together with holding the tape in a flat condition transversely and holding the wires spaced apart substantially parallel throughout the path of travel of the .is formed from material that is readily fusible yuponfitself uponpapplication of heat :z-it is through the .euse iiofasuch; imateriali that't e method forming the subiectsmatterzof; this :in-

.the -.sequence.1set forth. =Aocording y,: understood that such-changesxand@modifieatiens vention, is =made;p ossib-1e. .A speciallyformed sand highlysdesirableaslat-gis produced, quickly and eefficiently if. these; stepstare followed and. ,obvi- .ously; they said stepszare'zall interconnected :duete the. fact that the precise; speedzof v travel =,of the tapeand wires, the..stretching-;.action, the heat applying means rand ethe iholding -;.and feeding structure for the tape andrwiresboth-before and after joinder thereon-must-..operate simultaneouslyiand in.conjunction.onewith. the vother be- :forea slat can .be produced as ,easily'andquickly as ;iSL- possible A through this method.

@It is eappreciatedtthat -:;many qother methods might .-.We1l sbe USHdiJQO produce-the :filat. but 1 th ,aadvantages hEFBOfifii-B apparent-sand; it will :be ap'preciated .:a {tremendously glarge rnumber pf slats can be produced in a shortierigth ofgtime: if the. steps "are! followedas; herein outlined and in toibe of the; stepssof: thezmethodl form neethe subiect matter of: this 1 inventionsas iia-i y :cQme

the scope of; the, appended :cla i ns, tare contemplated zhereby.

Having thus I described :the inventionwhat I .claim aslnew andtdesirestmsecure by Letters .Patent is:

1. Thex methodof .prqducing venetian hlind slats which comprises continuously: f eejdi-n-g :3 flat flexible .tape along ;.a predeteltmine :pa :o travel; simultaneously feeding ;a their ;of wires .along one face .-of1.the itape; :foldingrportions :of the tape over. the wires andsjoining saidportions along one face ofthetape maintaining-sai d;.tape only in. a a stretched condition; longitudinally: :as the sameais fed; randi ioiningzther; wires andzthe 1 tapebwhile the: tape isistretched.

iBJ -The method 10f i-prodncing izvenetian :sblind slats-which comprises:continuouslydeedingsaiflat .ifl xibl ,l132;pe'-.al()ng;2, :xpredetermined path -:.of

travel; flsimultaneously l feeding a pair :of wires along one faceaof z thei: tape at. aispeed differing from the-speed ofitra-velirof the tape;i=m'aintaining said tape st-retched nlongitudinally :as 1the same-is i ed; (ands; o'ining the wires 1 and; the tape while the tape is stretched.

4. The method of producing Venetian :zblind slats whichcomprises:continuouslyzifeeding'aflat flexible tape along a predetermined epath r of travel;-simultaneously feeding a .pair 'of wires along one face of the tape;'foldinguportionsxof the tape over the-wires; adhesively joiningwsaid portions it of the tape to said one face thereofias the wires andthe tape-progress together; and

w holding said portions nfthetape tightly.1-aga-inst said one face thereof :While' -adhesivelyljoining the same.

5. In the method of producing Venetlam blind slats which includes nontinuouslypulling. avlflat;

flexible tape along a predetermined --path sof travel; "progressively increasing' the pulling force onthe tape asthe -fedend thereof is approached whereby to maintain-said tape stretchedalon'gitudinally; simultaneously -feeding reinforcing thereto and means --alongone -face of the tape; 1 and ajoining "1 2. v-stretched; and :as the tape andthe means; .progtess to ethe 7 6. The a-inethod of iproduci-ng -:-Venetian blind slats which comprises.continuously feedingraz :fiat, flexible tape along :a 1.:predetermined i=pat-h eof travelxsaid:ttapeirbeingtformed from: matenialreapab le of fusing upon itself .upon. -applicationeof wheat: thereto; simultaneousl feeding; a gpa-ir iof wires along; one face ofzthetape ;-;folding;:portions of the taper rovertthezwires mappl'vine heat? tozithe tape for; fusing:rsaidzportionsgoftthei tapeutoysaid one. face thereof ifiilidsPIGSSiIlQ: said: portions-20f .the tape tightly :against said :one: face r thereof while heating: thezsame and (while feeding tithe tapeandthe wires.

7. The method of .pneducing Nenetianblind slatswhich'comprisescontinuously'feedingzaffiat, flexible tape ialong T131 :qpredetermined rpa'th 0f travel, .said tape-being formedfromzmaterial: capable. of": fusing upon; itself ZHDOI'IiTfiDpIiQatiQII-IOf heat "thereto; simultaneously: feeding a: pair 20f ewires along tone: faceaoftthe' tape; folding portions of the tape over the wires; applying'heattotthe tape for fusing :saidhportionssoftthe tapezto'asaid =one face thereof; and'tholding tsaid :izpor'ti'ons :of

' the tape tightly against said :one iface thereof before and aftenappLicatiOn -ofzsaidz heat thereto. 8. The :method :=-of1:pro'ducing Nenetianeblind slats-which comprises continuous-lyieedinglaiflat, flexible tape -.:along: a'iz'predetermined inpath eof trav'el, said tape b'eing formed from material 1 5 cap able-of fusing upon itseltzupon application of heat thereto; simiiltaneouslyfifeeding :a I pair of wires along one taceof the i tape; holding-said wires spaced 1 apart arid 'spaced I from proximal 4 marginal edges respectively- 0fsaid' tape; folding said marginal edges 0f the: tapesover -corresponding Wires; -applying heat-to the tape *for'fusing said marginal edges to said-one face :orthe tape; and applyi-ng pressure to saidtape por tions and to the opposite face of said' tapeiduring fusing for holding the-tape in tight engagement -wi th the-wires.

-9.' T-he -=method of prdducing enetian blind slats which comprises guiding flexible tape alonga-rectilinear pathef travel str'etehingsaid tape longitudinally along a portion er its length; feeding a -'-pair: -of'-=wires in spaced relationship along =one face -of -'the tape at su-bstantially the same rate of speed as the-"speed of travel-6f the tape; -jo ining the wires *andthe'tapemlong the stretched lengthbf the latter ;--releasinga portion of the tapejoinedtothe Wir-es' f-rom -said stretchingaction; andsevering' a part- 0f said porti-on of the" tape and of the wires j oinewthereto*into predetermined -Slat'iengths.

IOIThe method of -producing' venetian blind slats whichcomprises-guiding va fleXib1e**tape alonga-rectilinear path of-travely stretching said tape longitudinallyalong a portion nfits length;

"feeding a pair of wires in spaced relationship along one face of 'the tape-at"substantial ly"the same rate-of "speed; asthespeedhftravel of the tape; Y joining thewires and the-tapealongthe stretchecltlength "ofthelatter; releasing a portion of the tape joindtothe Wiresfrom-saidstretching' action; supporting saidfportion er the tape and 'the" wiresijoined" thereto "in--21; severing position; severing apart: of said portion'nfthe tape and of the"wires"joined thereto "into --predetermined slat-lengths; *andrieleasing-the slat from said supportedpos'ition.

(References on following page) References Cited in the file of this patent UNITED STATES PATENTS Number Name Date Barrett Sept, 19, 1893 Barrett Sept. 19, 1893 Brown Nov. 9, 1920 Meeker Aug. 16, 1932 Balthasar Aug. 31, 1937 Houghton Jan. 14, 1941 Burns Dec. 8, 1942 Number Number 10 497,788 

1. THE METHOD OF PRODUCING VENETIAN BLIND SLATS WHICH COMPRISES CONTINUOUSLY FEEDING A FLAT FLEXIBLE TAPE ALONG A PREDETERMINED PATH OF TRAVEL; SIMULTANEOUSLY FEEDING A PAIR OF WIRES ALONG ONE FACE OF THE TAPE; FOLDING PORTIONS OF THE TAPE OVER THE WIRES; AND JOINING SAID PORTIONS OF THE TAPE TO SAID ONE FACE THEREOF AS THE WIRES AND THE TAPE PROGRESS TOGETHER. 